There were lots of times, especially in the early days, that were very, very difficult. I think the most difficult experience I had was in 1990 when Oracle had its only loss quarter in history. We’d been in business for 20 years, and after 20 years we lost money one quarter. We had a very difficult time. We had virtually doubled our sales every year for ten years. Nine out of ten years, ten out of eleven years. It was really quite an amazing run. We were the fastest growing company in history

I would say there are many challenges, and that's kind of what's hard about it. And my particular thesis, since leaving Google and doing my own company, is that building a quantum computer is a little bit harder than the scientists think about because of the system engineering. Building a powerful computer is hard. So what we're particularly working on is the manufacturing of qubits and doing that much better than what people are doing right now. I really enjoyed being in academia, and even at Google working on that. But I really enjoy right now trying to think very practically about what we have to do to get this to work. And what kind of people we have to collaborate with in order to put all the pieces together and build a quantum computer in a cost effective, economic way that makes business sense.

Then you have the clients. The care and feeding of clients is really one of the main obstacles, because you always have a client with some preconceived idea of what a house looks like, and all you want him to do is leave a check and go to Europe for a couple of years. Or leave two checks. But alas, life isn’t simple. If it were, more people would be better architects.

In terms of this issue of these industrial gases affecting the environment, at the beginning the road was not easy, because we were suggesting that society had to change, that industries had to do something different than they were doing at that time. And of course, initially we did not meet with a good reception to these ideas from industry. And even from the scientific community — even though our ideas were well received in the small group of specialists in what we were doing — it was not necessarily well received by the scientific community at large. So we really had to continue doing as good a science as we could, and at the same time trying to well communicate our conviction that it was something important, something that had to change in the way society was functioning.

It's not possible to get any distance from my project: being alive. Objectively, from the outside you might say, my life is terrible, unbelievable. And it's true, I hate this. I hate the way I am at the moment. But there is no objective view, I am here, in it, and there is nothing else, and this fact brings with it many things that make it of course easier. And beyond that there are many other things to think about.

I think that loss of speech, and of understanding of speech, and of understanding of writing, and of coherent writing – these losses will amount to the loss of my mind. I know what this feels like and it has no insides, no internal echo. Mind means talking to oneself. There wouldn't be any secret mind surviving in me.

The mystery of summoning up words. Where are they in the mind, in the brain? They appear to be an agency from nowhere. They exist somewhere in our ground or in our air. They come from unknown darkness. From a place we normally don't think about.

It is a very rare affliction. A GP would expect to meet it once in a career and this form of brain cancer is unpredictable and dangerous. Usually, this tumour might give you only a two-year span since its discovery. I have had two operations and one course of radiotherapy and now three chemotherapies (one currently starting). My death is, in a sense, imminent. I say to myself: I am dying. Something in my head is hurrying to kill me.