That's one way of looking at it

I've been thinking about – among other things (hence my failure to add to the Harmless Drudgery mountain (slag heap?) for the best part of  two weeks) – obsession. In particular I've been thinking about what obsession, gunwale, and titanic have in  common.

People with an etymological bent (sic – I‘m reminded of Joni  Mitchell‘s ‘That  girl is twisted‘) – will be familiar with the random arising of questions such as "What‘s obsession got to do with sitting?‘

<grandmothers_egg_sucking>
(And I know it should be grandmothers', but the compiler wouldn't be able to handle apostrophes; I know the compiler is a figment of my imagination, but if a conceit‘s worth pursuing it‘s worth pursuing to the last syllabub of recorded time.) 

Words built from some variant of "session" (not -cession, which is a whole 'nother kettle of worms) include somewhere along the line the idea of sitting. At its simplest, for example, a court that  is  ‘in session‘  is sitting.  Session musicians "sit in". And the Holy See involves sitting on a particular sort of chair (whence the building that houses it, a cathedral, gets its name). 

<RC_note>
Ex cathedra pronouncements are reserved for when the Pope Really Really Means It.
<RC_note> 

Etymonline‘s entry for "obsess" explains further:
</grandmothers_egg_sucking>

So besieging – the now obsolete meaning of obsession – involves an army encircling a town and just sitting it out. (I discussed words to do with sitting a while ago, here.) If you think of the poor besieged  townsfolk,  who can‘t get anywhere, by any path, without coming up against the besieging force, you can see where the modern sense comes from: any thought leads to the same place  – the obsession (the besieging enemy).

So ob and sedere got together to concoct the military  meaning, and psychotherapy took the ball and ran with it – so successfully that the ‘besieging‘ idea withered on the vine: obsession isn't just a metaphor; it‘s a metaphor that turned into another metaphor with a totally different meaning.

Which brings me to  gunwale, commonly reduced to gunnel. Most  native speakers of English have met the expression "laden to the gunnels" (OK make that ‘about a third of us, with the other two thirds saying "packed to the gunnels"). The gunnel is a wide plank at the edge of the deck, and if a ship is laden to the gunnels its load is so heavy that the ship  is low in the water.

But if you peel back the superficial metaphor (and when I said "plank" I was giving the game away, as today wood need not  be involved and often isn't) you find out what the gun is doing. On a sailing ship intended for battle the edge of the deck was reinforced with an especially sturdy plank, which supported the cannon – the gun wale.

<further_reading>
Pick the bones out of this if you're interested in the wale bit.
</further_reading>

Like obsession, gunnel (in expressions such as "laden/full to the gunnels") started life as a metaphor, and was pressed into use as another totally different metaphor.

You can probably see where I‘m going with this; the story with titanic is similar. I‘ll just sketch out the bare bones:

Titans (powerful gods) 👉 titanic (=big and powerful) 👉 Titanic: big/powerful ship

Along comes an iceberg and one metaphor gets flipped on its head to make another: something that‘s titanic can either be big/strong/influential ("a titanic struggle") or it can have a capital T and be over-confident and doomed to failure.

There must be more such metaphors  that have been given a new lease of life as newly formed metaphors, but this has gone on long enough...

<autobiographical_note>
(as has this accursed backup)
</autobiographical_note>

.. and I  must return to the land  of the living.

b