Despite our scientific and philosophical knowledge, it is still difficult to accept that we are alone in the Universe and that our self will vanish with our death.

Hitherto the conception of chemical transmission at nerve endings and neuronal synapses, originating in Loewi's discovery, and with the extension that the work of my colleagues has been able to give to it, can claim one practical result, in the specific, though alas only short, alleviation of the condition of myasthenia gravis, by eserine and its synthetic analogues.

The history of science is the back-and-forth movement of trial-and-error advances and retreats, punctuated by moments of brilliance and marred by periods of excess.

One brain’s blueprint may promote joy more readily than most; in another, pessimism reigns. Whether happiness infuses or eludes a person depends, in part, on the DNA he has chanced to receive. (152)

When people have trouble with their emotions – a bout of anxiety or depression, say, or seasonal gloominess - they often want science to pinpoint an offending neurotransmitter in the way that a witness picks the perp out of a lineup. Is it excessive norepinephrine, too little dopamine, errant estrogen? The answer is apt to dissatisfy: no single suspect can be fingered with confidence because the question itself attributes a fallacious simplicity to the brain.(91)

Much like addictive drugs, power uses ready-made reward circuitries in the brain, producing extreme pleasure.

There must be some supreme creative energy, he thought, that can take love and turn it into synapses and then take a population of synapses and turn it into love. The hand of God must be there

The part of my brain that was responsible for creating the world I lived and moved in and for taking the raw data that came in through my senses and fashioning it into a meaningful universe: that part of my brain was down, and out. And yet despite all of this, I had been alive, and aware, truly aware, in a universe characterized above all by love, consciousness, and reality. There was, for me, simply no arguing this fact. I knew it so completely that I ached.

The problem is, when you depend on a substitute for love, you can never get enough.

We—each of us—are intricately, irremovably connected to the larger universe. It is our true home, and thinking that this physical world is all that matters is like shutting oneself up in a small closet and imagining that there is nothing else out beyond it.