One of the most significant influences on my childhood was my grandmother, who was born in 1889. Until 1955, she owned and operated a kitchenware shop while also practising as an herbalist. She possessed extensive knowledge of medicinal plants, wild foods, traditional remedies, and practical household skills. At certain times of the year, she would go out to gather herbs and other plants, including beard lichen from coniferous trees, traditionally valued for its antimicrobial properties. She was sometimes accompanied by other knowledgeable people, among them a pharmacist. Through these experiences, she taught me not only to recognize medicinal plants and understand their traditional uses, but also to distinguish carefully between what was beneficial or edible and what could be poisonous.
Her knowledge extended far beyond medicinal herbs. She taught me to recognize poisonous plants, distinguish edible wild mushrooms from dangerous species, and appreciate the nutritional value of foods found in nature. She spoke, for example, of elderberries as a source of vitamin C and antioxidant compounds, and valued hazelnuts for nutrients such as folate, or vitamin B9, and copper. As a result, my early understanding of the natural world was never confined to medicine. Plants could serve as remedies, sources of nourishment, useful materials, or serious hazards, depending on their properties and how they were handled and used.
She made these distinctions concrete through everyday experience. I learned to recognize particularly dangerous plants, including autumn crocus (Colchicum autumnale) and foxglove (Digitalis), both of which can be highly poisonous. She also took me with her when buying flour directly from the mill and explained why grain had to be carefully cleaned to remove ergot, historically known as Secale cornutum and called Mutterkorn in German, before milling. Lessons such as these impressed upon me from an early age that knowledge of the natural world was not merely interesting or useful; at times, it was essential for personal safety.
My grandmother also passed on practical knowledge rooted in a broader tradition of self-sufficiency and craftsmanship. She taught me, as well as other women in the town, how to select the finest yearling wool and how to pick, wash, prepare, and care for it before spinning. Such work required patience, close observation, and a thorough understanding of the qualities of natural materials. Through this kind of instruction, I came to understand that knowledge was not simply something to be explained or memorized. It was acquired through attention, experience, careful handling, and repeated practice.
Central to my grandmother’s teaching was a clear understanding of the proper place of medicinal plants and natural remedies. Having lived through the Spanish Flu pandemic, she believed that such remedies could support the body’s own healing processes, particularly when symptoms first appeared, but she did not regard herbs as the source of healing itself. Just as importantly, she understood their limitations. Some illnesses, she taught me, required forms of medical treatment that herbs could not provide. Respect for traditional remedies therefore had to be accompanied by sound judgment: knowing when they might be appropriate, recognizing when they were insufficient, and understanding when medical treatment was necessary.
This balance between knowledge and caution was perhaps the most enduring lesson she passed on to me. Her teaching combined respect for traditional knowledge with careful observation, practical experience, and an awareness of its limits. From her, I learned to approach the natural world neither with unquestioning faith nor with dismissal, but with curiosity, respect, and discernment.
My grandfather, born in 1888, added another dimension to this early education. He inherited responsibility for a 12-kilometre stretch of the Wörnitz River in Germany, where he cared for the health of its fish populations and the surrounding riverbank ecosystem. His responsibilities included observing the river’s flora and fauna and protecting extensive reed zones (Röhrichtzonen), where common reed (Phragmites australis) and other wetland plants grew along the shallow water’s edge. These areas provided important habitats and breeding grounds for fish, waterfowl, and many other species.
From him, I learned to see the river not simply as a source of fish or other resources, but as an interconnected living system in which water, plants, animals, and human activity all influenced one another. He taught me which fish he considered suitable or unsuitable for eating, as well as which plants should be avoided or handled with caution. He strongly discouraged us from eating carp and catfish because, in his view, their bottom-feeding habits made them undesirable as food. Whether or not all of these traditional judgments correspond with present-day scientific understanding, the underlying principle of his teaching remained important: before deciding whether and how an organism should be used, one should understand its habitat, behaviour, and place within the larger ecosystem.
He also taught me about useful wetland plants such as cattail (Typha), different parts of which have traditionally served a variety of purposes. Some have been used as wild food, while others have served as natural insulation or stuffing material. Cattails also perform important ecological functions in wetlands, helping to retain nutrients and sediments while providing shelter and habitat for wildlife. Even when dried, these plants could be put to practical use. Through such examples, I learned that a single species could possess ecological, nutritional, and practical significance at the same time.
My grandfather’s concern for the river went beyond observation and traditional knowledge; it extended to public health and active environmental protection. Having served as a soldier in France during the First World War, he had witnessed the devastating consequences of infectious disease, including the deaths of many soldiers during the Spanish Flu pandemic. These experiences left him acutely aware of the importance of sanitation and of the dangers associated with contaminated environments. Although the scientific understanding of viruses and their transmission was far less developed at the time than it is today, he understood in practical terms that human health depended in part on maintaining clean surroundings and protecting sources of water from contamination.
This awareness informed his efforts to protect the Wörnitz. He was one of three local people who successfully advocated for regulations intended to prevent untreated waste from being discharged directly into the river. These measures prohibited household toilet waste from houses built immediately along the riverbank from flowing directly into the water and prevented farmers from disposing of cow manure in the river. For him, protecting the river was therefore not simply a matter of preserving fish or vegetation. It was also a matter of sanitation, community health, and responsibility toward the people and animals that depended upon the river.
He was particularly concerned about the consequences of excessive nutrients entering the water. Today, we understand that nutrient pollution can contribute to eutrophication, creating conditions that favour blooms of blue-green algae, more accurately known as cyanobacteria. Some cyanobacterial blooms can produce toxins that pose risks to humans and animals through skin contact, accidental ingestion, or exposure to contaminated water droplets. Long before I understood the scientific processes involved, my grandfather gave us a simple and memorable rule based on practical observation: never swim in water when a green algal bloom was visible.
His lessons therefore went far beyond identifying individual plants, fish, or hazards. He taught me to recognize relationships: between the quality of the water and the organisms living in it; between sanitation and human health; between human activity and environmental consequences; and between careful observation and responsible stewardship. His knowledge had been shaped not only by life along the river, but also by experiences of war, disease, agriculture, and community responsibility.
From him, I learned that protecting nature required more than appreciating it. It required understanding how living systems functioned, observing changes carefully, recognizing the consequences of human interference, and being willing to act when those systems were threatened. In this respect, his teaching complemented that of my grandmother: both taught me that practical knowledge of the natural world carried with it a responsibility to use that knowledge carefully, to recognize danger, and to protect both human health and the environment.
Their efforts helped protect the river’s water quality and preserve the surrounding ecosystem. For me, this became a lesson of lasting importance because it demonstrated that protecting nature sometimes requires more than individual knowledge and responsible behaviour. It can also require collective action, community involvement, and rules designed to safeguard a shared resource. In retrospect, what my grandfather taught me through practical experience anticipated principles I would later understand in scientific terms: human activity, water quality, ecosystem health, and human health are closely interconnected.
Looking back, I recognize that both of my grandparents approached knowledge through a combination of inherited understanding, practical experience, and careful observation of the natural world. Whether identifying medicinal or poisonous plants, distinguishing edible mushrooms, evaluating wild foods, preparing wool for spinning, observing fish populations, or protecting a river ecosystem, they demonstrated the same underlying habit: understand what you are dealing with before you act. They also taught me, both implicitly and explicitly, that knowledge has limits and that sound judgment begins with recognizing them.
These early lessons became a foundation for the way I have approached problems and important decisions throughout my life. I came to understand that sound judgment requires more than information alone. It calls for observation, practical experience, an awareness of both possibilities and limitations, and a willingness to consider different forms of evidence before reaching a conclusion. What my grandparents gave me, therefore, was more than an appreciation of medicinal plants, nutrition, craftsmanship, and the natural environment. They gave me an early understanding of the interdependence of ecosystems, traditional knowledge, human health, and responsible decision-making.
Other lessons became equally enduring parts of my inheritance from them. I was taught to prepare for difficult times and to ask for help only when it was truly needed; to share freely, without expecting gratitude or reward, what I had learned with those willing to listen; and to recognize when to set boundaries with those convinced that they already knew everything.
I also learned not to be seduced by what was merely cheap, but to seek lasting quality and genuine value in what I chose to acquire. Above all, I was taught never to deny myself the opportunity to learn more: to remain critical of what I was told and willing to question even what I believed I knew.
Knowledge, once gained and tested, carried a responsibility of its own. One had to have the courage to stand by what one had learned and by what one knew to be right. To surrender that judgment merely for convenience, approval, or conformity would mean surrendering something more important: one’s self-respect.
Perhaps most importantly, my grandparents taught me a way of thinking: observe first, understand the context, recognize the limits of one’s knowledge, and only then decide. Their example joined self-reliance with a willingness to accept help, generosity with personal boundaries, and openness to new knowledge with critical judgment. These principles have continued to guide my thinking and decision-making throughout my life. They have also left me with an enduring awareness that certainty should be approached with humility and that what has not yet been demonstrated should not automatically be dismissed. As the principle is often expressed, “absence of evidence is not necessarily evidence of absence.”