re: #39 Trumpia est omnis divisa in duo calathi(Sophist)

Not could, would. Any change at all would ripple outward, and alter pretty much everything. For instance, because which, if any, of 200 million sperm fertilizer a human embryo can be changed so easily, anyone who went back 100 years ago and affected people in any way would assure that nobody alive today would exist. Instead, there would be seven billion other people on earth.

IOW, a time traveler could be a mass murderer on a global scale.