The words conscience and consciousness can cause a good deal of confusion, due in some measure to the similarities in their spelling and pronunciation, so let’s have a proper look at them.
Conscience /ˈkɒnʃəns/ can mean one of the two things:
the part of your mind that tells you whether what you are doing is morally right or wrong; i.e. we can call it our inner moral compass.
I knew I’d done nothing wrong and so I told him the truth with a clear conscience.
If you’ve done something you shouldn’t and know it, you probably have a guilty or troubled conscience.
Steve’s guilty/troubled conscience made him tell Anna he’d been cheating on her.
The guilty feeling itself is also called conscience. That’s the second meaning.
I felt a sudden pang of conscience when I realized I hadn’t called my parents for nearly a month.
Another useful expression is (to have something) on your conscience, meaning that you feel guilty about something bad you’ve done.
At least I can say quite confidently that his bankruptcy is not on my conscience – I did my best to talk him out of investing all his savings in that dubious start-up but he wouldn’t listen.
Now over to consciousness /ˈkɒnʃəsnəs/. To add to confusion, it also has multiple meanings.
Firstly, consciousness is the state of being awake and aware of what is happening around you.
Running after the bus, she stumbled over a dent in the pavement, fell, hit her head and lost consciousness.
Other verbs you can use with consciousness in this sense are regain, recover and return.
He regained/recovered consciousness before the ambulance arrived.
When she returned to consciousness, she found herself in a hospital ward surrounded by doctors and nurses.
Secondly, and this is where I guess most confusion happens, consciousness can refer to mind and thoughts as a whole.
I dare say it’s our unique consciousness that distinguishes us from other animals.
Hope I’ve been successful in clarifying the differences between conscience and consciousness and they’ll never cause you any confusion.