Well, I'd like to chime in here to support Colin -- I love spiders, and have made it clear to the Big Calamari and the Squidling that I do not want them killed in our home. (Two exceptions would be black widows and brown recluses, both of which are seriously venomous.) I see spiders as totems of creativity, and have no problem holding them unless they are dangerously venomous (all spiders, like all Octos, have venom, but not all are dangerous to humans) and/or aggressive (or as Croc Hunter would put it, "bitey"). Plus they kill other, less desirable "visitors" such as cockroaches.
That being said.... I loathe centipedes. They are the only creepy-crawlies in whose extinction I would willingly participate. (Well, maybe scorpions too, but there aren't too many of those in my part of the US.) Why? I don't know. They kill other vermin, just like spiders do. I was never bitten by a centipede either. There's just something about those segments and those legs.... Then again, I don't mind millipedes. Go figure!
Regarding Prism's comment about His Holiness the Dalai Lama -- for whom, BTW, I have the deepest reverence and admiration: Are you aware of the fact that all Tibetan Buddhists, including HHTDL, eat meat, including mammals and poultry? The reason for this is that the land of Tibet, being at a high altitude and very cold, is inimical to most crops with the exception of barley (which is made into sticky cakes called tsampa). So traditionally, Tibetan Buddhists would supplement their diet with meat from either yaks or other mammals killed by a fall (not uncommon in such a mountainous region), or from Muslim butchers (who, in the Buddhists' eyes, would reap the bad karma from killing the animals, thereby absolving themselves). This may seem hypocritical to us, but to Tibetans it was a matter of life and death.
Later, when a large percentage of Tibetans -- including His Holiness and other Lamas, Monks, and Nuns -- were driven out of their land by the Chinese Communists, these diaspora Buddhists continued to consume meat (including meat from commercial sources) even though they lived in countries like India and the US where vegetarian food was easily accessible. So while Tibetan Buddhists will try at all costs to spare the lives of all beings, they make the exception of beings killed for food. In this, they differ from all other Buddhist sects.
BTW, many years ago I had a friend named Ulka who was a Gujarati Jain, with whom I hung out while our kids played together (she and her family later moved away from here). Jains are strict lacto-vegetarians who are not even permitted to eat free-range eggs lest they contain a viable embryo. The idea of trying not to step on bugs -- which may seem ridiculous even to some vegetarians here -- was a very real issue to Jains. In India, many of the most devout ones carry soft brooms to sweep the ground before them when they walk, so as to avoid stepping on insects in their path. Before they boil water, they strain it through cloth so that no small living things in it will be boiled to death (considering what the water is like in many parts of India, it's probably a good idea anyway).
I was at Ulka's apartment here a couple of times, and it was scrupulously clean except for the fact that there were several cockroaches running around! I assume they were either foraging for stored food or escaping from nearby apartments that had been fumigated for bugs. In any event, Ulka made no attempt to kill them or even call an exterminator. Cockroaches in a Noo Yawk apartment are no surprise -- we've dealt with them ourselves -- but refusing to kill them was something I'd never seen before. However, I am not a Jain so I cannot pass judgment on their customs. (In case you're wondering, yes, I did have lunch at her place and it was very delicious, very fresh, and cockroach-free.)
So ultimately I think the idea of what is or is not acceptable to eat, is purely subjective. I personally would draw the line at eating any animal alive -- but then again, I've eaten clams and oysters on the half-shell, and how "dead" are they, really, after just being shucked? (On the other hand, how sentient is a bivalve, even a live one?) I don't know about Octopus in ink. However, as for the Cuban dish calamares en su tinta (Squid in their own ink), I've had this and found it delicious. As far as I know, the Squid is dead and on ice long before cooking, and the ink bladder is removed from the dead Squid during cleaning and gutting. I no longer eat Cephs simply because I regard them as a sort of personal totem, but if there were nothing else to eat I would consider them a legitimate food source.
I assume all of us would draw the line at cannibalism. But what if -- like a South American soccer team whose plane went down in the Andes many years ago -- there was nothing to eat except the bodies of your already-dead fellow travelers? As long as you didn't have to kill anyone, would you sacrifice your own life by wasting protein that would be eaten by worms anyway? (Even if one believes in a soul, which I do, doesn't the cast-off mortal body become part of the earth after death, like a butterfly's chrysalis?) And what about heart, liver, and (some) kidney recipients -- in a sense, don't they "consume" the bodies of the dead donors, so that they themselves might live?
Difficult questions, to which IMHO there are no set answers. A very good thread for philosophical, ethical, and environmental discussion!
Pax et bonum,
Tani