The universe is seen as highly fine-tuned. There are certain universal laws of physics which can be applied throughout the cosmos that we know so far. However, it is often misconstrued that life would not exist on Earth if a single variable was different: if the Sun was closer or farther away, if the atmosphere was thinner or had a different chemical composition, if the Earth’s days were longer or considerably shorter etc. This fallacy is known as the Weak Anthropic Principle.
All that tweaking these variables will mean is that life as we know it will probably not have existed, not life in general. We do not yet know what fundamental conditions would rule out the possibility of life. Even bacteria, such as D.rad, have been shown to survive in the most barren and extreme conditions. For all we know there could be intelligent beings on another planet arguing that a weak gravitational force is an essential component to life.
Life is fine-tuned to the cosmos, not vice-versa. This is what evolution proposes. If the universe was indeed fine-tuned for life then surely life would not be quite such a rare part of it. It is quite possible that, though it is unlikely that we are the only forms of life in the galaxy, homo sapiens are the only intelligent beings in the Milky Way. This possibility has been thoroughly explored by John D. Barrow, a cosmologist, and Frank J. Tipler, a mathematical physicist, in the book The Anthropic Cosmological Principle.
The Anthropic Principle is further weakened when one considers the fact that different initial conditions sometimes lead to essentially the same outcomes, as with the initial mass of stars and their formation of heavy metals.
The idea that life can only exist if it is based on the same chemical properties as ourselves is a highly restrictive view and has been called Carbon Chauvinism. The term “anthropic” in the name of the principle is also commonly seen to be a misnomer since anthropic means “of or pertaining to mankind or humans,” which is inherently biased since it does not factor in a consideration of bacteria which could lead to higher life forms, it singles out our kind of carbon-based life forms, and a prerequisite development of intelligence is implied before one considers the life they have discovered to be “life.”