If we can see further today it’s because we’ve been standing on the shoulders of giants. This is certainly true of the veg movement. One of those giants is Frances Moore Lappé, author of the wildly popular book, “Diet for a Small Planet”, which came out 50 years ago and yet even today its influence is still being widely felt.

Lappé explained that a vegetarian diet was much better for the planet and was healthy for us. Ms. Lappé was 25 and attending graduate school at the University of California, Berkeley, when she began to question her life’s purpose. Like many in her generation, she was inspired by the ecological movement that led to the first Earth Day.

Vegetarianism in those days was considered an unfamiliar way of nourishing oneself to the mainstream. The center of the American dinner plate was reserved for a big pork chop or steak. In the introduction to one edition of “Diet for a Small Planet” she recalls promoting the book on a local Pittsburgh TV talk show in the mid-1970s. Ms. Lappé was booked alongside a U.F.O. expert, and her only question from the host was: “What do you think they eat on U.F.O.s?” I doubt any host today would be that clueless.

If you ate a Tofurky this Thanksgiving rather than an actual bird, in a way you can thank Ms. Lappé. The inventor of Tofurky, Seth Tibbot, read “Diet for a Small Planet” and, as he told the makers of a documentary about the future of food, it changed his life. Ethan Brown, the founder of Beyond Meat, is another disciple. And, of course, you could count the author herself among those whose life was radically changed by the ideas within “Diet for a Small Planet.”

Despite her success — her book has sold more than three million copies through several editions, and she was named a recipient of the Right Livelihood Award, a kind of alternative Nobel Prize — Frances is a down-to-earth, cheerful woman of 77.

However, we must note one error that she made. In her first edition she said that people had to combine proteins at each meal such as eating beans with corn, to get the right balance of amino acids. That turns out not to be true, eating a range of plant-based protein sources over a few days will give you all the amino acids you need, you don’t need to eat them all in one meal. To her credit, in every subsequent edition of the book she has emphasized that this was a mistake.