I do get the 'blank canvas' thing, that's the first sensible anti tattoo argument I've heard.
Beyond that, I think we should bear in mind that social mores are fluid - I'm a teacher in a management role at a private international school. I have a tattoo (which I love) which I usually do cover up as I don't like the fact that only part of it shows when I wear short sleeves. So long or 3/4 sleeves for work, sleeveless if I want my tattoo on display - & sleeveless wouldn't be appropriate for workwear, tattoo or not.
So I'd say go ahead with the tattoo, with the caveat that you may find it bugs you if it restricts what you can wear.
I'm a good teacher, my skills are in demand & I can afford not to work in a school where my tattoo, brightly dyed hair & piercings would be a pearl clutchy deal breaker.
But I would think it naive not to think it will impact on the reactions some, more conservative individuals will have. I don't have to agree with them, but I do have to take it into account.
My solution is that there are 'on duty' & 'off duty' versions of how I present myself. A tattoo that I couldn't hide whilst wearing normal, comfortable workwear would be more of a nuisance than piercings & hair dye - I could remove the studs & dye my hair brown tonight if I chose to.
Planning a bloody awesome sleeve for my retirement present to me, though
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