Philosophers of science, faced with the puzzle of how life might emerge from dead matter or how conscious beings might evolve from microbes, have developed two types of explanations.
The first consists of what's called emergentism. The argument here is that once a certain level of complexity is reached, there is a kind of qualitative leap where completely new sorts of physical laws can "emerge"—ones that are premised on, but cannot be reduced to, what came before. In this way, the laws of chemistry can be said to be emergent from physics: the laws of chemistry presuppose the laws of physics, but can't simply be reduced to them. In the same way, the laws of biology emerge from chemistry: one obviously needs to understand the chemical components of a fish to understand how it swims, but chemical components will never provide a full explanation. In the same way, the human mind can be said to be emergent from the cells that make it up.
Those who hold the second position, usually called panpsychism or panexperientialism, agree that all this may be true but argue that emergence is not enough. As British philosopher Galen Strawson recently put it, to imagine that one can travel from insensate matter to a being capable of discussing the existence of insensate matter in a mere two jumps is simply to make emergence do too much work. Something has to be there already, on every level of material existence, even that of subatomic particles—something, however minimal and embryonic, that does some of the things we are used to thinking of life (and even mind) as doing—in order for that something to be organized on more and more complex levels to eventually produce self-conscious beings. That "something" might be very minimal indeed: some very rudimentary sense of responsiveness to one's environment, something like anticipation, something like memory. However rudimentary, it would have to exist for self-organizing systems like atoms or molecules to self-organize in the first place.
— David Graeber,
"What's the Point If We Can't Have Fun?"