Well there certainly are demerits to science and technology. War and accidents come to mind, as well as certain negative societal changes.
New technology is used for war, like nuclear weapons. Accidents happen, like Chernobyl. Culture change happens too, such as that cars have caused pollution and obesity in America.
But I wouldn't ever discredit the need for science or technology. It is what drives our society, and what makes living easier.
For consumers, the demerits of technology are vast. Consumers are drawn increasingly indoors to their entertainment centers and are desensitized.
Science, in itself, doesn't have any demerits except for the fact that you can never be done proving something right because all it takes is one new fact to make it utterly wrong.
The world of technology has gotten us into space and helped us explore the rest of our own world, but it has also desensitized youth and created a world where the mind is being wasted (at least in the United States) as well as the body (at least in the United States). People need to not forget to exercise both their mind and body in order to be able to survive in the harsh and apocalyptic world that may loom ahead.
The risks associated with human nature (abuse & self-gratification incurring long term costs) and incomplete knowledge.
EXAMPLE: Nuclear fission
Â MERITS: Energy supply with less carbon-footprint
Â Â DEMERITS due to incomplete knowledge:
Â Â Â Side effects of radioactive waste
Â Â Â Â Â http://en.wikipedia.org/wiki/Chernobyl_accident
Â DEMERITS due to human nature:
Â Â Â Enriched plutonium used to create bombs
Â Â Â Â Â http://en.wikipedia.org/wiki/Fat_Man
There are none! Any issues that people or society have with science and technology are due to how they use them, rather than with them directly!
LUDDITES - ARISE !